to update your from wp 7 to wp 7.5 you have to download zuna software and install it to ur system then connect your phone USB to it. make sure your phone is fully charge. the software will detect an update. good luck

The phone on itself is not so bad. The OS is either not bad. The biggest issue I have with the hd7 are the poor antennas in the device. Wifi reception is not up to par with the most other devices from that generation. Cellular signal is even worse altough I have the most optimal radio firmware installed. Opening the case and checking the cables for wifi didn't reveil anything special. The antenna for the cellular signal is behind the bottom cover that protects the sim and internal sd card. My phone has now deepshining custom rom v8 installed which is beneficial for the user experience. HTC build quality is more than ok and battery lasts several years.
Naturally, you can't compare this phone with the latest galaxy range or htc 2012/2013 android phones